Add profile support for Zero-Wait DFS on select FortiAP models 7.6.4

This information is also available in the FortiWiFi and FortiAP 7.6 Configuration Guide: Configuring Zero-Wait DFS.

This release expands Zero-Wait Dynamic Frequency Selection (DFS) availability from FAP-U platforms to QCA-based FAP F, G, and K models equipped with 4x4 or 8x8 MIMO radios.

The FortiAP must be running firmware version 7.6.3 or later to support this feature.

Under standard DFS behavior, when a radar is detected on a DFS channel, the AP has to stop transmission and perform a 60-second Channel Availability Check (CAC) on the new channel before resuming service. This can lead to client disconnections and service downtime.

Zero-Wait DFS minimizes downtime during DFS events by enabling the AP to switch channels immediately after radar detection without waiting for the 60-second CAC. When Zero-Wait DFS is enabled, the AP scans DFS channels in one of two modes:

• RCAC mode – FCC/MKK: The AP selects and pre-scans a backup channel. Once a radar is detected on the operating channel, the AP radio moves to backup channel and starts service right away, skipping CAC.

• Pre-CAC mode – ETSI: The AP scans all the DFS-configured channels one by one in the background, looking for CACs and clearing them in advance. Once a radar is detected on the operating channel, the AP radio moves to a new channel. The AP checks the CAC status of the new channel, and if it is already cleared, it starts service right away, skipping CAC.

The following CLI configuration setting has been added:

config wireless-controller wtp-profile
  edit <name>
    config <radio>
      set zero-wait-dfs [enable|disable]
    end
  next
end

zero-wait-dfs

Enable/Disable Zero-Wait DFS on a 5GHz radio (default = enabled).

To configure Zero-Wait DFS on a FortiAP:

1. Create a FortiAP profile with zero-wait-dfs enabled under a 5GHz radio.

   config wireless-controller wtp-profile
     edit FAP431F-default-ZwDFS
       config platform
         set type 431F
       end
       config radio-2
         set zero-wait-dfs enable
       end
     next
   end

2. Apply the FortiAP profile to a FortiAP.

   config wireless-controller wtp
     edit FP431FTF23021146
       set wtp-profile FAP431F-default-ZwDFS
     next
   end

To verify that Zero-Wait DFS is applied:

1. From the FortiGate, enter the following diagnose command:

   # diagnose wireless-controller wlac -c wtp FP431FTF23021146 | grep zero
       zero wait dfs    : enabled

2. From the FortiAP, enter the following diagnose command:

   # cw_diag -c zwdfs
       Radio-1 : zwdfs(rCAC)=Enable , DFS-Domain=1, rcac_freq=5620(124)